Download the specific BlackBerry OS 7.1 or 7.0 build meant for the BlackBerry 9790. These files typically end in an .exe extension (e.g., 9790M_PBr7.1.0_rel2108.exe ). You can download these from archival sites or carrier support hubs.
Right-click and it. If you find a second vendor.xml file in your user data directory ( AppData\Roaming\Research In Motion\BlackBerry\Loader ), delete that one too. Step 3: Wipe the Device (Optional but Recommended) Firmware Change Update on BLACKBERRY 9790 Bold
Select the applications and languages you wish to include, then click Initialization : The process can take 20–30 minutes. Do Download the specific BlackBerry OS 7